Doorbell



FIG. 1 is a front and side perspective view of a doorbell embodying the new design;

FIG. 2 is a back and side perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a back view thereof;

FIG. 5 is a first side view thereof, the second side view being a mirror image;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The dash-dot-dash lines represent the boundary of the claimed design. Uniform repeating broken lines show a surface feature around a camera, a doorbell button, and the back of the design. The dash-dot-dash lines and the uniform repeating broken lines form no part of the claimed design. 

CLAIM The ornamental design for a doorbell, as shown and described. 